Mk12 Mod 0 SPR Precision Reflex (PRI) Upper Receiver Group standard in FDE

MSRP: $1,777.00
(You save $48.00 )
Made to Order at Factory - Ships in 5 to 8 weeks

PRI Mk12 Mod 0 SPR Upper Receiver Group (URG) - FDE

This is the PRI standard configuration URG for the Mark 12 Mod 0 - 18" Mark 12 Mod 0 SPR Upper in FDE Finish 5.56 Cal.

PRI originally supplied the US Navy at NSWC Crane with the round forearm free floating handguard for the SPR rifle, which became the Mk12 Mod0.  This is a recreation of the original rifle, with parts from PRI, Douglas Barrels and other mil-spec providers. Crane had originally produced the Mk12 upper receivers from commercial parts providers, like Precision Reflex.  At the beginning of the War on Terror, when M4 parts were in short supply for regular ground forces, Crane was forced to take out of mothballs M16 A1 lower receivers to mate to the custom uppers that Crane built.  Later versions of the Mk12 were found with lower receivers from Colt, Armalite, LMT and regular issue M4.

This Mark 12 Mod 0 is built with PRI's Retro Gen II, which is most representative of the early Mk12 upper receiver groups.  Originally, all Mk12s were black, but many found their way to be painted (rattle caned) or Cerakoted FDE.  This reproduction is a great addition, and the FDE Cerakoting is done very nicely, and will match most any black or FDE / Tan / Taupe M4 lower receiver.

This upper comes tested by PRI and ready to shoot 5.56mm NATO ammo.  Charlie's recommends 77 grain Black Hills or Federal.  The upper is equipped with a 18" Douglas 416 stainless steel barrel with a fitted bolt and commercial carrier, flat-top receiver, PRi flip up front gas block front sight with thumb screw elevation adjustment and PRI rear sight, rifle length gas tube, a Gas Buster charging handle with big latch, and a AE inc brake and collar. The system also comes with a Gen II Rifle length carbon fiber free float forearm in Black finish and a full length Picatinny top rail. This upper comes with a black barrel. 

Your choice of 1:8 or 1:7 twist.  Precision Reflex provides this reproduction with nice mix of period correct parts, PRI branded parts, and commercially available mil-spec parts to offer the history buff or shooting enthusiast with a good balance between authenticity, performance and price.


Caliber 5.56/.223
Upper Receiver PRI branded logo / mil-spc forged T6 7075 with hard coat anodizing
Barrel 18"  5.56 NATO chamber Douglas 416 stainless 1:8 twist or 1:7 twist, branded PRI
Gas Block PRI flip-up front sight gas block with two cross bolts
Forearm PRI Gen2 rifle length round tube with Picitinny top rail
BUIS PRI rear flip-up sight
Muzzle Device Allen Engineering / Ops Inc. brake and collar to fit AEM-5 and #12 suppressor.
Bolt Carrier Group mil-spec phosphated BCG with Carpenter Steel bolt
Top Rail Swan Rail made by PRI
Charging Handle PRI M84 Gas Buster 
Length & Weight 27" / 5-1/4 pounds


Accuracy is based on barrel type    5.56 Douglas  sub MOA

Standard on all PRi rifles and uppers are the Gas Buster Charging Handle with Military latch.